A first approach to the molecular phylogeny of the genusEchinops (Asteraceae): Sectional delimitation and relationships with the genusAcantholepis

A first attempt to establish the phylogeny of the generaEchinops andAcantholepis has been carried out using the analysis of the internal transcribed spacers (ITS) sequences of the nuclear ribosomal DNA including 30Echinops species and the only species of the monotypicAcantholepis. The results of this analysis are discussed in the light of morphological and cytogenetic characters. The genusAcantholepis is placed in a robust clade withEchinops nanus, and together they appear in a basal position to other members ofEchinops. The ITS phylogeny and several other characters, such as chromosome number and nuclear DNA amount, do not agree with the sections currently recognized withinEchinops. Some groups are defined in the present approach, but further studies are necessary to reach a complete, stable and natural infrageneric classification of this genus.